Method of making tires and apparatus therefor.



J. A. SWINEHART.

. METHOD OF MAKING TIRES AND APPARATUS THEREFOR.

APPLICATION FILED MAY 16, 1913.

1, 1 22,333. Patented Dec. 29, 1914.

, 2 SHEETS-SHEET 1.

I .FL/o .Z a n ZZMMW J. A. SWINEHART.

METHOD OF MAKING TIRES AND APPARATUS THEREFOR.

APPLICATION FILED MAY 16, 1913.

1,1 22,333. Patented Dec. 29, 1914.

2 SHEETS-SHEET 2.

WW: Elna-arm JAMES A. swninHART, oFs'r. LOUIS, MISSOURI.

Specification of Letters Patent.

Patented Dec. 2a, 1914.

Application filed May 16, 1913. Serial No. 767,960.

To all whom it may concern:

Be it known that I, JAMES A. SWINEHART, a citizen of.the United States,residing at the city of St. Louis and State of Missouri, have inventedcertain new and useful Improvements inMethods of Making Tires andApparatus Therefor, ofwhich the following is a specification.

In the present method of curing tires for automobiles and the like, in,which the tires are built by hand on a form, then placed in a mold andhydraulic pressure applied from the inside of the tire to expand samewithin the mold while the tire is being cured, it sometimes happens thata tire becomes defective during the curing process,on account of thefailure to permit the excess of pressure within the tire to escapebefore the tireis destroyed within the mold.

It is the object of the present invention to provide an improved processand apparatus for curing or vulcanizing tires which will allow anyexcess of pressure within the tire to escape automatically and therebyobviate the possibility of breaking the tire, thus insuring theproduction of a tire free of any defects.

In the accompanying drawings forming part of this specifi cation, inwhich like numbers of reference denote like parts wherever they occur,Figure 1 is a side elevation, partly in. section, of a hydraulicvulcanizing press of the jacketed type; Fig.2 is a plan view of one ofthe tire molds; Fig. 3 is a sectional view, on an enlarged scale, on theline 38' Fig. 2; Fig. 4 is a similar view showing a modification.

In this improved process of curing. or vulcanizing the tires, ahydraulic vulcanizing press 1 of the jacketed type is preferablyemployed, having the steam inlet pipe 2 and the outlet pipe 3. Thehydraulic. ram 4 within the press is operated by the pressure of fluidwhich is forced through pipe 5 into the lower part ofthe press by a pump(not shown). The press is provided with a re movable cover 6 which ispreferably constructed as shown and described in United States LettersPatent-No. 955,739, granted to Alexander Adamson, April 19, 1910, sothat same can be locked in a closed position during the vulcanizingprocess.

The molds 7 in which the tires 8 are placed to be cured or Vulcanizedare placed one on top of another upon the head 9 of the ram 4, asclearly shown in Fig. 1. Each mold comprises two separate annularmembers 10', which are connected by bolts 11, which pass throughopenings in lugs 12 on the outer and inner peripheral faces of saidmembers as depicted in Figs. 2 and 8, these bolts being relativelyshorter than the thickness ofthe mold. The opposed faces of the members10 have annular grooves 13, respect1vely,.formed therein, which groovesregister with. each other and form the walls of an annular opening, inwhich the tire 8 is placed to be expanded agiinst the walls thereof.Each member 10 also has an annular member 14 fitted into an annulargroove 15 in. its inner face, which member 14 has an annular groove 16in its inner face to receive one of the tire beads 17. The fabric ofwhich the tire is formed is left long enough to project a little beyondthe beads 17 as at 18, and between these edges 18 is placed apackingring 19, which has a pipe 20 cona space 22 between the members10. The molds 7 with the tires 8 filled with water therein are placedone on top of another upon the head 9 of the ram 4: and then the cover 6of'the press is closed and locked. Fluid from the pump is then admittedto the ram 4, so as'to cause the latter to press the molds 7 against thecover. 6 and, also, to press the members 10 of, each mold closertogether. vSteam being admitted through the pipe 2 into the presscirculates around the molds 7 and heats the water within the tires, withthe result that the Water within the tires expands and presses the tiresagainst the inner walls of the molds. The

pump is run at a speed to cause the head '9, of the ram 4: to exert apredetermined pressure against the molds, and wheneverv the water in atire 8 expands sufficiently to exceed the pressure of the ram themembers 10 of the mold 7 containing said tire will be forced apart, withthe result. of not only forcing the ram downward, but also pertheprojecting edges 18 of the tire 8,1eaving.

mittin g the excess of pressure within the tire to escape between thepacking ring 19 and the edges 18 of the tire, after which the ram risesand again presses the member closer together as before, thereby closingthe escapement for the water within the tire and keeping same closeduntil the water within the tireagain expands sufficiently to exceed thepressure of the ram.

It will be evident that by means of curing tires in the mannerhereinabove described, the excess of pressure within the tires isallowed to escape automatically, whereby the tire is prevented frombeing broken or destroyed during the curing or vulcanizing of same.

In the form of the invention depicted in Fig. ithe check-valve 21 isomitted entirely and a relief-valve 23 of any suitable construction,substituted therefor. In this form, it is unnecessary to use thehydraulic ram 4. The relief-valve 23.will open automatically and willallow the excess of pressure within the tire to escape therefrom.

I claim:

1. The herein-described method of curing tires in a hydraulicvulcanizing press consisting in inflating a tire between the separableparts of a mold with fluid, placing the mold with the inflated tiretherein in the press, maintaining a uniform temperature within thepress, and automatically maintaining a uniform pressure of the fluidwithin the tire by the pressure of the press ram.

2. In an apparatus for making tires, the combination with a moldcomposed of connected separable parts between which a tire is placed andinflated with fluid, means in terposed between the edges of the tire toretain the fluid in the tire, and ajacketed vulcanizer in which the moldwith the inflated tire therein is placed, of means adapted to press theparts of the mold together within the vulcanizer and to permit theescapement of some of the fluid from the tire, when the pressure of thefluid within the tire exceeds a predetermined pressure.

3. In an apparatus for making tires, the combination with a moldcomposed of con nected separable parts between which a tire is placedand inflated with fluid, means interposed between the edges of the tireto retain the fluid in the tire, and a jacketed vulcanizer in which themold with the inflated tire therein is placed, of hydraulic meansadapted, to press the parts of the mold together within the vulcanizerand to permit the escapement of some of the fluid from the tire, whenthe pressure of the fluid within the tire exceeds a predeterminedpressure.

4. In an apparatus for making tires, the combination with a moldcomposed of connected separable parts between which a tire is placed andinflated with fluid, means in terposed between the edges of the tire tore tain the fluid in the tire, and a jacketed vulcanizer in which themold with the inflated tire therein is placed, of means for instantlypermitting some of the fluid to escape automatically from the tire, whenthere is an excess of pressure within the latter.

5. In an apparatus for making tires, the combination of a moldcomprising a pair of separate members adapted to receive between them afluid-inflated tire; means interposed between the edges of the tire forretaining the fluid therein; a jacketed vulcanizer' wherein the moldwith the inflated tire therein is placed; and means connecting the moldmembers together and'with which said members are movably engaged,wherebv said members are free to separate automatically when thepressure of the fluid within the tire exceeds a' predetermined pressure,to permit some of the fluid to escape.

6. in an apparatus for making tires, the combination of a moldcomprising a pair of separate companion members adapted to receive atire between them and provided with oppositely-located apertured lugs;means for supplying inflating fluid to the interior of the tire, saidmeans being provided with a check valve; a jacketed vulcanizer whereinthe mold with the inflated tire therein is placed; andbolts looselypassed through the apertures in opposed lugs for connecting the moldmembers together, whereby said meinbers are free to separateautomatically when the pressure of the fluid within the tire exceeds apredetermined pressure, to permit some of the fluid to escape.

In testimony whereof I hereunto aflix my signature in the presence oftwo witnesses.

JAMES A. SWINEHART.

ffitnesses GLAurs WALTON, GEORGE G. Annnnson.

